SYNTHESIS OF 1,2,3-TRIAZOLO-QUINOLIZIDINES BASED ON THE QUINOLIZIDINE ALKALOID LUPININE

Abstract

The modification of the quinolysin alkaloid lupinine was carried out with the introduction of 1,2,3-triazolyl substituents for the hydroxymethylene group in the C-1 position of the quinolysin backbone. The reaction of lupinine with methanesulfochloride in the presence of triethylamine smoothly led to lupinine methanesulfonate, whose further reaction with sodium azide in DMFA led to lupinilazide. 1,3-Dipolar [4+2]-cycloaddition of the resulting azide to alkynes produced more stable 1,2,3-triazole compounds. The interaction of lupinilazide with 2-ethinylpyridine and with alcohols containing a terminal acetylene group (propargyl alcohol, 2-methylbutyl-3-in-2-ol or hex-5-in-1-ol) proceeded smoothly in the DMFA medium. The reactions were carried out in the presence of an aqueous solution of CiSO₄ and sodium ascorbate in DMFA and allowed the corresponding 4-substituted (1S,9aR)-1H-1,2,3-triazol-1-yl to be synthesized with good yields)methyl)octahydro-1H-quinolysins. The results of studying the structural features of synthesized compounds by ¹H - and ¹³C-NMR spectroscopy, as well as data from the two-dimensional COZY (¹H-¹H) and HMQC (¹H-¹³C) spectra are presented. The values of chemical shifts, multiplicity and integral intensity of ¹H and ¹³C signals in one-dimensional NMR spectra are determined. In the spectra of all synthesized new quinolizidinotriazoles, there is a peak of the fragmentary C₁₀H₁₇N ion (150-151 cu), corresponding to the cleavage of the molecule by the C-10 atom of the quinolizidine backbone.